The Japanese say that, “When the wind blows the barrel-maker gets rich”.
What they mean is that a seemingly innocent cause can have far-reaching and apparently unrelated effects.

When the wind blows, it whirls up dust. Some people get this dust into their eyes, and a very few of them lose their eyesight.

The traditional occupation for blind people in Japan was to tell stories and play the shamisen, a traditional Japanese instrument. A shamisen is a stringed instrument and the skin is made of cat skin (or sometimes dog skin but this is rarer). So to make shamisens for all the blind people, you would kill a lot of cats.

With fewer cats, the rats and mice thrive, and people will want barrels in which to keep their produce safe. And so the barrel-maker becomes rich.

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A case in point, as told by the late Libertarian Harry Browne: In early 1917, World War I had raged for almost three years in Europe. Millions had died at the front lines, more millions had died or suffered behind the front. And the governments of the warring nations were coming to the realization that even if they could win (technically, on the battlefields), the price of victory would be prohibitively high. Germany and Austria-Hungary had sent out feelers for a negotiated peace on the Western front, and neither England nor France were adverse to this.

A few months earlier, Woodrow Wilson had been inaugurated for his second term as President of the United States of America, on (among other things) promises to keep the USA out of the war in Europe. He broke that promise by entering the European war in April 1917, strengthening the French and English resolve. They rejected the German and Austrian-Hungarian peace proposals, instead demanding an unconditional surrender.

The following year, in 1918, Germany and the Austro-Hungarian Empire were forced to surrender on humiliating terms. In the meantime, however, the war had sparked the Russian revolutions of 1917, bringing the Bolsheviks to power in Russia. In fact, the Germans helped Lenin travel to Russia to lead the revolution in November (October by the Russian calendar; hence the name “The October Revolution”). If they hadn’t been pressed on the Western front, maybe they would have kept Lenin where he could do no harm and Russia – and ultimately Eastern Europe – would have been spared the years of “communist” dictatorship. We would probably not have heard of Lenin or Stalin (except maybe that the latter had been executed for robbing a stagecoach, which was how Stalin made a living before turning to politics).

Following the German and Austro-Hungarian defeat, Austria-Hungary split up into Austria, Hungary, and Czechoslovakia. Germany was badly humiliated and nearly bancrupted by demands for “reparations”, and the emperor was forced to resign. A negotiated peace in 1917 would have kept him in power, and Germany would have remained a monarchy rather than a democracy for some years more. More importantly, the humiliation and economical devastation caused rampant nationalism and eventually would allow Hitler and the National Socialists to rise to power. The Treaty of Versailles became the first stepping stone towards Nazi Germany, and World War 2. Without the American intervention, Hitler would have been reduced to hanging wallpaper.

If only Woodrow Wilson had kept his campaign promises…

Could Wilson have known this? No! That is the whole point. He didn’t know that his “well-meaning” attempt to fix Europe’s problems would eventually bring two of the 20th century’s worst dictators to power. But he could have left Europe to solve its own problems, as he should have!